methylene

French méthylène, from Ancient Greek μέθυ (méthu, “wine”) + ὕλη (húlē, “wood”). By surface analysis, meth- +‎ -ylene.

• IPA^(key): /ˈmɛθɪliːn/

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methylene (countable and uncountable, plural methylenes)

1. (organic chemistry) The divalent group –CH₂– in which the free valencies are part of single bonds.
2. (organic chemistry) The same group, present as a repeating unit, in aliphatic compounds with names such as hexamethylenediamine.
3. (organic chemistry) The unstable carbene :CH₂

• methylene on Wikipedia.Wikipedia